‘I was stunned when the pieces started falling into place,’ recalls specialist Howard Dixon of the moment an unassuming folio of photographs was presented to him in a restaurant in Texas earlier this year.

On the seventh page, a small photograph showed a medieval Italian broadsword — a piece which bore a striking resemblance to another that had been mysteriously missing since the 1940s. Until that moment, says Dixon, ‘no one knew where it had gone, and the trail had gone cold.’

In this video, Dixon reveals how a ‘twin’ sword in New York’s Metropolitan Museum of Art helped trace the Harriet Dean sword’s history back to 15th century Cyprus — describing what it felt like to make ‘a once in a lifetime discovery.’